In detergent compositions, various surfactants are used according to the application purposes thereof, and many of such detergent compositions have a foam quality rough and lacking elasticity. Widely used detergent compositions containing polyoxyethylene alkyl ether sulfates or alkyl sulfates are excellent detergent compositions in the sense that such detergent compositions are excellent in foaming and are hardly affected by water quality; however, such detergent compositions are inferior in foam quality to detergent compositions including soaps as the fundamental ingredients thereof to bring about elastic and creamy foams having fine particle sizes. If such foam qualities, rough and lacking elasticity, of polyoxyethylene alkyl ether sulfates or alkyl sulfates can be improved into creamy foam qualities and detergent compositions excellent in storage stability can thereby be obtained, various formulations can be designed, and such formulations as detergent compositions are useful as body detergents for the skin or hair preferring creamy foam quality.
In Patent Document 1, it is disclosed that a liquid detergent containing micellar-growth-promoting agents such as a non-soap anionic surfactant, an amphoteric surfactant, a nonionic surfactant having an HLB of 6 to 18 and a higher alcohol is excellent in detergency and satisfactory in low-temperature stability. In Patent Document 2, it is disclosed that a hair detergent containing a sulfate residue-containing anionic surfactant, a higher alcohol having 10 to 14 carbon atoms and a cationic polymer has a foam quality satisfactory in foaming and slippability at the time of cleansing the hair, has a smooth feeling at the time of rinsing the hair, and is excellent in feeling of use. In Patent Document 3, it is disclosed that a detergent composition including an anionic surfactant, a specific nonionic surfactant and water and taking a gel or liquid crystalline form is highly viscous, satisfactory in resistance to sagging at the time of dealing with hand or a tool and nevertheless satisfactory in spreading performance, high in storage stability, and quick and satisfactory in foaming. In Patent Document 4, it is disclosed that a hair detergent including a sulfate surfactant, an alkyl glyceryl ether, silicone oil, a cationic polymer and myristyl alcohol brings about a foam quality satisfactory in foaming and slippability, smooth feeling at the time of rinsing, and gloss and well-shapedness to the finished hair, and is satisfactory in low-temperature stability and weakly irritant.
However, none of these detergent compositions simultaneously satisfies the foam quality improvement and the storage stability. In the detergent composition including a polyoxyethylene alkyl ether sulfate or an alkyl sulfate, a technique is adopted in which a higher alcohol is added for the purpose of attaining creamy foam quality; however, the storage stability of this composition is not sufficiently satisfactory. Additionally, the conditioning shampoo in Example 9 of Patent Document 4 cannot bring about creamy foam.    Patent Document 1: JP-A-2004-91522    Patent Document 2: JP-A-2003-212733    Patent Document 3: JP-A-2004-168951    Patent Document 4: EP 1676566 A